ABSTRACT
BACKGROUND: At present, inflammation is considered to be one of the key players in the development and maintenance of atherosclerosis, with ample impact on renal transplant outcomes. Interleukin-6 (IL-6) levels and the underlying genetically determined "high-producer" status impact cardiovascular morbidity and mortality. In end-stage renal disease (ESRD) patients, the role of genetically determined IL-6 differences in cardiovascular and renal outcomes of kidney transplantation is controversial. In this study, we sought to clarify the influence of IL-6 haplotypes on cardiovascular and renal outcomes among kidney transplant recipients. METHODS: Three hundred fifty-two first kidney transplant patients were genotyped for the two "clade" IL-6 polymorphisms ((-174)G/C and (1888)G/T) and two missense polymorphisms (Pro32Ser, Asp162Val), which are known to influence IL-6 levels and outcome. RESULTS: We observed four IL-6 haplotypes among our population: CCAG: 57.0%, CCAT: 2.8%, GCAT: 39.2%, GCTT: 1.0%. After stratifying the haplotypes into diplotypes in three different models, we failed to observe associations with early or late graft outcomes, or with all-cause or cardiovascular mortality. These findings were also confirmed when we separately analyzed each polymorphism. CONCLUSION: Despite evidence of associations in other transplant and ESRD cohorts, we could not confirm any association between IL-6 haplotypes/diplotypes and cardiovascular or graft-related outcomes among our population at high risk for inflammatory diseases.
Subject(s)
Cardiovascular Diseases/epidemiology , Interleukin-6/genetics , Kidney Transplantation/adverse effects , Adult , Aged , Cardiovascular Diseases/genetics , Female , Follow-Up Studies , Graft Rejection/epidemiology , Graft Survival , HLA Antigens/genetics , Haplotypes , Histocompatibility Testing , Humans , Interleukin-6/blood , Kidney Function Tests , Kidney Transplantation/mortality , Kidney Transplantation/physiology , Male , Middle Aged , Polymorphism, Single Nucleotide , Postoperative Complications/epidemiology , Retrospective Studies , Time FactorsABSTRACT
BACKGROUND: Transplant renal artery stenosis (TRAS) is a frequent complication after renal transplantation, however long-term follow-up data after interventional treatment are rare. PATIENTS: In our transplant center 11 of 264 consecutive renal transplant recipients (4.17%) were diagnosed with TRAS. In addition, TRAS occurred in 2 renal transplant recipients that had been transplanted at other centers but who had their follow-up examinations in our center. Either a rise of the serum creatinine level and/or worsened systemic hypertension or routine examination with color Doppler sonography were indications for further diagnostic workup. METHODS: Direct angiography of the transplant renal artery was performed followed by percutaneous transluminal angioplasty (PTA) after the diagnosis of TRAS was confirmed in all of these patients. RESULTS: The immediate success rate for PTA was 92.3% (12/13). Only 1 patient with a severe kinking of the transplant renal artery had to undergo surgery to restore renal function. No complications occurred after the interventions. Thereafter the patients were monitored for a mean observation period of 33.15 months. Serum creatinine levels were significantly lower after the intervention, and estimated glomerular filtration rate (eGFR) increased accordingly. With regard to blood pressure there was only a trend for lower blood pressure levels and less antihypertensive use, whereas the dose of the prescribed drugs decreased significantly with time after interventional treatment of TRAS. In addition, a long-lasting rise of the hemoglobin levels could also be demonstrated. CONCLUSION: In summary, the beneficial effect of PTA of TRAS on renal function is long-lasting. Therefore, PTA, usually combined with stent placement, should be first-line treatment in TRAS in all patients. Surgical revascularization is only warranted, if PTA fails.
